Contractions help
I have done extensive tests with contractions & O2 consumption. The results of my experiments are clear:
1. While getting contractions, you consume LESS OXYGEN than while NOT getting contractions.
This is why Martin always tried to get contractions as SOON AS POSSIBLE!!
I will give an example. If I hyperventilate and then do a static, I reach 5'00 without even being close to a contraction, and according to the oximeter my SaO2 is 82% (very consistent and repeatable). In this case I would start at around 100% or 99%.
If, however, I take just 2 BREATHS (!!), and then pack the same amount, then I get my first contraction at 3'30 (and at the start I would be at SaO2 = 98%). Then, by the time I have reached 5'00, I have been getting contractions for 1'30, but my SaO2 is 90%, which is far higher than 82%, due to the nonlinear progression of this curve (even though I started off at a lower SaO2 in the beginning). Similarly, when I reach 6'00, my SaO2 is much higher if I got my first contraction at 3'30 rather than at 5'30 - 6'00.
By not hyperventilating, your CO2 is much higher, and the high CO2 drops your metabolic rate so much that it makes up for the muscular effort of the contraction. Plus, the CO2 stimulates the vagus nerve and drops your heart rate along with your metabolic rate.
When I did my pb of 7'35, I think I was at SaO2 = 84% at 5'00 (this was with hyperventilating). When I take just 2 or 3 breaths, then I'm at 90% after 5'00, which means, in theory, that I could far surpass my pb; the problem is always that after 6'00 - 6'10 (without hyperventilating), my CO2 goes over 9.2% and I cannot hold my breath anymore, and I must exhale. Martin, however, managed to continue holding his breath despite CO2 > 9.2% (he probably went over 10%). After CO2 = 9.0%, I start to get CO2 narcosis, even during dry statics!
Eric Fattah
BC, Canada